FIX: Input State Window is now force-closed when the device it is inspecting is disconnected

Packages/com.unity.inputsystem/CHANGELOG.md

@@ -34,6 +34,7 @@ however, it has to be formatted properly to pass verification tests.
 - Fixed an issue with default device selection when adding new Control Scheme.
 - Fixed an issue where action map delegates were not updated when the asset already assigned to the PlayerInput component were changed [ISXB-711](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-711).
 - Fixed Action properties edition in the UI Toolkit version of the Input Actions Asset editor. [ISXB-1277](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-1277)
+- Fixed an editor crash caused by input debugger device state window reusing cached state when reconnecting Stadia controller. [ISXB-658](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-658)
 
 ### Changed
 - Added back the InputManager to InputSystem project-wide asset migration code with performance improvement (ISX-2086).

Packages/com.unity.inputsystem/InputSystem/Editor/Internal/InputStateWindow.cs

@@ -113,6 +113,26 @@ public unsafe void InitializeWithControl(InputControl control)
             PollBuffersFromControl(control, selectBuffer: true);
 
             titleContent = new GUIContent(control.displayName);
+
+            InputSystem.onDeviceChange += OnDeviceChange;
+        }
+
+        private void OnDeviceChange(InputDevice device, InputDeviceChange change)
+        {
+            if (m_Control is null)
+                return;
+
+            if (device.deviceId != m_Control.device.deviceId)
+                return;
+
+            if (change == InputDeviceChange.Removed)
+                Close();
+        }
+
+        internal void OnDestroy()
+        {
+            if (m_Control != null)
+                InputSystem.onDeviceChange -= OnDeviceChange;
         }
 
         private unsafe void PollBuffersFromControl(InputControl control, bool selectBuffer = false)
@@ -286,6 +306,12 @@ private string FormatByte(byte value)
         ////TODO: support dumping multiple state side-by-side when comparing
         private void DrawHexDump()
         {
+            if (m_StateBuffers is null)
+                return;
+
+            if (m_StateBuffers[m_SelectedStateBuffer] is null)
+                return;
+
             m_HexDumpScrollPosition = EditorGUILayout.BeginScrollView(m_HexDumpScrollPosition);
 
             var stateBuffer = m_StateBuffers[m_SelectedStateBuffer];